Attaching Right Wing Rear Spar
The rear spar is attached to the right wing.
We attached the rear spar to the ribs and also installed the rear spar channel to attach the skin.
Rib Attachments
The rib attachments for the most part were straightforward, some rivets needed to be drilled out later since they were in the way of the rear channel, and they were re-installed after the rear channel was clecoed. Pictures of some ribs are shown below: 
Ribs 1 thru 5. 
Rib 6 rear view. 
Rib 6 front view. 
Rib 11 rear view. 
Rib 11 front view. 
Rib 13 rear view. 
Rib 13 front view.
Channel For Skin Attachment
The channel for the rear spar skin attachment comes in two pieces lengthwise. There is a thin plate in between to attach the two. However initially the plate was riveted on the wrong side, so those rivets had to be drilled out, consequently some holes got bigger, so it was replaced with 4.0mm rivets instead of 3.2mm for those holes. Additionally, the whole channel was riveted from root to the tip in sequence for the most part while strategically keeping clecos in between, then coming back and riveting those holes. 
Rear spar channel plate. 
Rear spar channel plate. 
Rear spar channel full view.